Negative Poisson's ratio in cubic materials along principal directions

This report employed molecular statics simulation and density-functional-theory calculation to study the Poisson's ratios of face-centered-cubic materials. We provide numerical and theoretical evidences to show that cubic materials can exhibit auxetic behavior in a principal direction under proper loading conditions. When a stress perpendicular to the loading direction is applied, cubic materials can exhibit a negative Poisson's ratio at finite strain. The negative Poisson's ratio behavior, including its direction and value, is highly dependent on the direction and magnitude of the transversely applied stresses. As a result, we show that it is possible to tune the direction and magnitude of the negative Poisson's ratio behavior of cubic materials by controlling the transverse loadings.